Electrical receptacle



R. B. BENJAMIN ELECTRICAL RECEPTACLE June 2. 1925. 1 ,540,o50

Filed Deo. 10, 1919 2 Sheets-Sheet 1 [NVEN TOR.

June 2, 1925.

R. B. BENJAMIN ELECTRICAL RECEPTACLE Filed Dec. 10, 1919 2 Sheets-Sheet 2 INVENTOR.

I: TTORNE)" Patented June 2, 1925.

UNITED srAre-s PATENT. ore-ice.

REUBEN B. BENJAMIN, or oHIcAeo, ILLINOIS, AssIGivoR. To BENJAMIN. nnncrnrc MANUFACTURING COMPANY, on CHICAGO, rnLrNorsgn C RPOR TION OF LLINOIS.

ELECTRICAL REGEPTACLE'.

Application filed December 10, 1919. Serial No. 343,757

To all whom it may concern:

Be it known that L'REUBEN. B. BnNJ-A-,

MIN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Electrical Receptacles, or which the following is a full, clear, concise, and exact description, reference being-had to the accompanying drawing, part of this specification.

My invention relates to electrical receptacles, and more particularly to pull switch sockets of the plug cluster type. i

One object of my invention is to provide improved switch supporting means whereby the switch mechanism is positioned for most ethlcient operation with a plug cluster type of pull switch socket.

Another object of my invention is to provide a plug cluster type of pull switch socket having a separate switch supporting means, whereby a rigid neat and compact arrangement of parts is provided.

Further. objects will appear from the detailed description to follow and from the appended claims.

In the drawings.

Fig. 1 is a vertical longitudinal sectional view of a plug cluster;

Fig. 2 is a sectional view on the line 22 of Fig. 1;

Fig. 3 is a sectional view on the line 33 of Fig. 1;

Fig. 4 is a sectional View on the line of Fig. 2;

the line 55 of Fig. 2; and

Fig. 6 is a portion of a sectional View on the line 66'0f Fig. 2. r

In order to give a general idea of my invention, it is here stated that the construction shown comprises a plug'cluster having a plug portion 10; a receptacle portion 11 and a switch base 12, all of which are held in position with respect to each other by means of a long conducting screw 13 which forms a part of the electrlcal connection between the plug and the switch mechanism 14.

The receptacle portion 11 comprises an insu'lating member 11* and shell contacts 15 on which are screwed the insulating bushings 16. The switch mechanism 1 1 is carried by the switch base 12 upon which also are forming a:

suitably. mounted the center contacts 17. Theswitch mechanism'comprises a switch for each receptacle and a plurality of pull chains 18 to. operate each switch independently.

To give a more detaileddescription of my construction, the plug receptacle 10 has suitably supportedthereon a threaded shell contact'19 which may be screwed intoa I suitable socket (not shown),

integrally formed with the threaded portionj'ofthe shell contact 19 is an inwardly extending flange portion 20, said flange portion having integrally formed therewith a downwardly extending finger 21, which fin ger extends downwardly into a recessed por-'.

tion 22 in the insulating portion 11*. Bearing against this finger 21 is a conducting member 23. having a hook portion 2a in te'grally formed therewith which is sprung into the recessed portion 22 and bears against the wall 25'thereof, thereby affording a positive andconstant electrical con nection between the conducting member 23 and the downwardly extendingfinger 21' of the plug shell contact; This conducting member 23 extends'downwardlyand is sup ported upon the insulating portion 11 by the screw 26 whereby it is electrically connected at its lower end with the V-shaped metal stamping 27 upon which are mounted the shell contacts 15. .7

shown, will allow for any inaccuracies in v manufacture of the porcelain parts and will Fig. 5 is a portlon of a sectional vlew onj shift to compensate for. these inaccuracies, and will at all times be in contact with the downwardly extending finger 21 of the plug shell contact,,thus 'aflor'ding a constant electrical connection between the plug and receptacle portions. c

As shown in Fig. 2, the receptacle portion 11 has offset recesses 28 and 28 in which the ends of the'insulating switch base 12 are positioned. This insulating base serves to receive and mount the electrical switch mechanism as well as the centercontacts 17.

The switch mechanism shown and de scribed herein is similar to that sho'wnfin the application of Benjamin Serial Number 326,831. The insulating base 12 is recessed as indicated at 29 to receive the switch op ioc tioned a switch shaft one end of which is rotatably mounted in a slot 31 cut in one of the walls of the chamber of the insulating base 12, the other end of the switch shaft being rigidly secured to a brush carrier 32.

The brush carrier 32 has the two cam surfaces 33 and 34, each substantially 180 de grees in extent. The cam surface 33 has a very slight and gradual rise, while the cam surface 34 has a comparatively large rise or lift which likewise is comparatively gradual. Both the cam surfaces 33 and 34 have an abrupt or sudden drop, or tooth 35 and 36 respectively. The switch shaft 30 is preferably secured to the brush carrier by embedding the end thereof'in the insulating.

material of which the brush carrier is constructed.

Mounted over the surface 33 of the brush carrier 32 is a brush member 37 which is provided with an arm 38 extending over the side face of the brush carrier to the axis thereof where said arm receives a hollow metallic cap 39 which ts over the projecting cylindrical boss 40 of the brush carrier. Said boss 40 and the enclosing metallic cap 39 constitutes a journal for. the brush carrier 32. The cap 39 is fitted in an aperture in a bracket 41 of conducting material which serves as a bearing for said journal. The bracket is secured to the insulating base 12 by means of a screw 42, the head of which supports the center contact 17.

The recess 29 has a narrow portion 43 in which is mounted a resilient U-shaped spring 44 which is normally biased by means of a spiral spring 45 in the direction of the brush carrier 32. The U-shaped spring 44 has one of its members 46 due to the aforesaid bias continually in contact with either the surfaces 34 of the brush carrier 32 or a brush member 37 thereon. Consequently the spring 44, depending'upon the position of the brush carrier, is either in contact with the brush member 37 as shown in Fig. 5 or with the insulating cam surface 34.

A sheet metal disk 47 is supported by the brush carrier 32 which disk carries a chain rail 48. The pull chain 18 rests in the chain rail 48 and engages a hook member 49 at its inner end. Consequently, when the pull chain 18 is operated, it will carry with it the brush carrier 32 which, in turn, will tension a spiral spring 50, which spring is can centrically disposed with respect to the switch shaft 30 and has the offset end thereof secured to a ledge provided for this purpose in the insulating base 12. The movement of the brush carrier is limited by a' projection 51 in the path thereof. The forward movement of said brush carrier under the actionofthe chain 18 will-be limment of said brush carrier will be limited by the engagement ofthe hook member 49 with said projection 51.

Due to this assembly of parts,twhen the chain 18 is pulled, the brush carrier 32 will rotate and will carry with it the chain rail 48 until the projection 52 thereof strikes the projection 51 on the insulating base. This marks the limit of the forward movement of the brush carrier and upon the release of the chain 18, the brush carrier will remain in the position to which it had been rotated, but the chain rail 48 and the flange 47 will be rotated in a reverse direction under the influence of the spring until the hook portion 49 strikes the projection 51 of the insulating base.

Since the arm 46 of the resilient U-shaped spring 44 is biased to be continually in con tact with either the brush member 37 or the insulating camsurface 34 of the brush carthe surface 34 and therebymove said spring in a direction away from said brush carrier and toward a contactingterminal 53. The movement of this U-shaped spring willtake place against the force exerted by the spring '45 and the rise in the cam surface 34 is such that the arm 46 of the U-shaped spring will move into contact with the contacting member 53 and the U-shaped spring will be considerably compressed before the high point iVhen on the cam surface 34 is reacheo. the high point onthe cam surface is reached, the end of the arm 46-of the U-shaped spring 44 will slide over the abrupt stop or shoulder 36 on to the brush member 37. Thereafter when the pulling force on the chain 18 is discontinued, the chain 18 will return to its normal position under-the action of the spring 50. Thebrush carrier 32, however, will remain in its advance position, being heldin this position by the end 46 of the vU-shape'd spring 44 which'rests against the top-or shoulder 36. WhGHlZhlS movement has been completed, the switch mechanism.

will be in the position shown in Fig. 5.

Upon the next operation of the switching mechanism bythe pulling of the chain 18 which results in the movement as hereinbcfore described, the arm 46 will ride over the brush member 37. Then the end of the brush member is reach-ed,rthere is an abrupt drop 35 whereby contact between the member46 of the U-shaped spring 44 and the brush member is first broken or interrupted, and thereafter under the action of the resiliency of the. U-shaped spring 44 and the biasing action of the spiral spring45, 111G111- ber46 will again come in contact with the c" insulating surface 34 of the brush carrier,

thereby breaking the contact between the member 46 or the U-shaped spring .44 and.

the contacting member 53.

It will now be evident that the cooperative action of the brush carrier and the 5.1-, shaped spring 44 is such that when the switch mechanism is moved from the open position to the closed position, the U-shaped spring will be torcedto the right so that the arm 46 thereof will contact with the contacting member 53. In this movement the cam surface 34 will gradually compress the two arms 46 and 46 of the U-shaped spring 44 and said arms will be under considerable compression when the high point of the cam surface 34 is reached, whereby good and positive contact will be obtained v and maintained between the arm 46 of the U-shaped spring and the contacting member 53.

When the arm 46 of the U-shaped spring reaches the high point of the cam surface 34 and passes over the stop, or shoulder 36, there will be a resulting slight expansion between the arms 46 and 4b of the U-shaped spring due to the slight stop at 36, but this expansion is so slight that good contact will stillvbe maintained between the arm 46 of the U-shaped spring and the contacting member 53, the arms 46 and 46 01 the UrSllEtPGd spring still beingin compression when in this position.

However, when the switch mechanism is operated fromi the closed position to the open position the arm46 of the U-shaped spring will ride over the brush member 37 until it reaches the abrupt drop at 35. This drop is a comparatively long one, the shoulder drop 35 being preferably made three or four times as large as the shoulder 36. Consequently when the arm 46 reaches the end of the brush member 37, the drop on the shoulder 35 is such as to permit the U- shaped spring 44 to expand freely due to its own resiliency and due to the force exerted by the spiral spring 45 whereby due to the drop, contact between the arm 46 and the brush is broken, and immediately thereafter the contact between the arm 46 of the U-shaped spring 44 and the contacting member 53 is broken.

The contacting member 53 has integrally formed therewith the substantially U- shaped member 54 which rests in a recess in the insulating base 12, and is held in said recess by an eyelet 55 (Fig. 1). The conducting screw 13 which supports the insulating base 12 extends through this eyelet and has a nut 56 thereon to firmly hold the switch base with relation to the conducting screw 13.

A sheet metal cup-shaped housing 58, hav-' the structure. A flange 59 is provided at the edge of this housing tofit over the lower edge of insulating member 11.

The circuit of the lamp socket may now be traced as follows: 7 i

Assuming that the switch mechanism is in its closed position, the circuit. is traceable ;trom the conducting screw 13through the eyelet 55, the U-shaped member 54 to the contacting member 53 and. thencethrough the U-shapedspring 44 and the brush. mem ber 37 by way of the conducting strip 38 to the metallic cap 39 which is in contact with the conducting bar 41 through the screw 42 to the center contact 17 of the lamp socket. With a lamp in position the circuit can be traced through the lamp to the threaded shell contact 15 and thence through the V-shaped metal stamping 27 through the screw 26, the conducting member 23, the

downwardly extending finger 21 and the plug shell contact 19 whichwill be in contact with a suitable receiving socket therefor; i

It will be evident that when the brush carrier 32 is rotated as hereinbefore described from the closed to the open position, that the circuit just traced will be opened at two points, first or primarily at the point oi contact between the member 46 of the U-shaped spring 44 and the brush 3'2, and secondarily and immediately. after the pri mary break, at the point of contact between the member 46 of the U-shziped spring and the contacting member 53 which is directly ten electricallyconnected to the long conducting screw 13. Likewise when the circuit is closed due to rotation of the brush carrier, contact will first be made between the member 46 of the U-shaped spring 44 and the contacting member 53, and thereafter when the member 46 of the Ushaped spring drops down from the high point of the brush carrier at 35,,the second contact ismade between the arm 46 and the brush 37 Consequently, when the circuit is'opened due to the operation of the switchingmechanism, the circuit will be broken practically simultaneously at two points, thereby very materially reducing the resulting sparking at the points of contact and consequently increasing materially the current carrying capacity of the switching mechanism.

It is evident from the foregoing description that this invention is made of very few. simply constructed parts which can be Very compactly assembled in the limited spaces available to the lamp socket and due to the simplicity of the construction of these parts,

the operation of the switch mechanism is exceedingly efiicient and reliable.

Obviously the invention is not limited to V the specific embodiments thereof herein il-' lustrated and described, but is capable of many variations and other applications within the spirit and scope of the invention as set forth in the following claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: V

1. A plug switch receptacle comprising plug contacts and receptacle contacts, said receptacle contacts comprising shell and center contacts, an insulating base on which the. plug contacts are mounted, a second integral insulating base on which the shell contacts are mounted and a third integral insulating base on which the center contacts are mounted, means for mechanically connecting said bases with respect to each other, and means mounted on said third indating base for controlling the electrical connection between said contacts.

2. A plug switch receptacle comprising a plug portion, a receptacle portion, an integral insulating switch base, switch mechanism and center contacts mounted on said switch base, said switch mechanism com prising a plurality of switches, acon'ducting screw supporting said switch base and having electrical connection with each of said switch mechanisms, said switch mechanisms making and breaking the'electrical connection between the conducting screw and each center contact independently of each other.

3. A plug switch receptacle comprising a plug portion, a receptacle portion comprising a plurality of shell and center contacts, a switch base having a reduced lower portion, switch mechanism supported by said base, said plurality ofcenter contacts being grouped around said reduced lower portion and said reduced lower portion forming a limit for the movement of the center contacts.

4?. A plug switch receptacle comprising a plug portion, a receptacle portioncomprising'a plurality of shell and center contacts, a switch base having a reduced lower portion, switch mechanism supported by said base, said plurality of center contacts being grouped around said reduced lower portion and said reduced lower portion forming a limit for the movement of the center contacts, said base having a large upper portion upon which said switch mechanism is supported. I

5. A pull switch plug cluster, comprising a plug portion and a receptacle portion, said plug portion comprising-an insulating base and shell and center contacts supported thereby, said receptacle portion comprisin a two-part insulating base having upper and lower portions, a switch mechanism supported between said upper and lower portions, a V-shaped member of conducting material supported by said receptacle base, said upper base portion having passages therethrough, and'conducting strips extending through said'passages electrically connecting the plug shell contact with the ti-shaped conducting strip and shell receptacle contacts supported by said V-shaped conducting member. p

In witness whereof, I have hereunto subscribed my name.

REUBEN B. BENJAMIN. 

